Steam jet pump



Nov. 27, 1934. J. GARVIE STEAM JET PUMP Filed Sept. 9, 1952 2Sheets-Sheet l INVENTOR. Jn N56 Gmzv/r.v PER. Hrromzv.

J. GARVIE STEAM JET PUMP Nov. 27, 1934.

Patented Nov. 27, 1934 UNITED STATES 1,982,378 STEAM JET PUMP JamesGarvie, Bedford Park, London, England Application September 9, 1932,

Serial No. 632,465

In Great Britain October 20, 1931 3 Claims. (01. 230-95) My presentinvention relates to improved means for eliminating smoke and, improvingthermal efficiency of boilers. Heretofore various efforts have been madeto eliminate smoke and improve thermal efliciency by employing steam andair blast apparatus in which a nozzle connected to a source of steamsupply projects ajet of steam into a Venturi nozzle and is locatedwithin a tubular jacket or sleeve provided with air admission apertures.It is found that with apparatus of this type as at present in use thereis a tendency to use it as little as possible because of the excessivenoise set up by the action of thesteam jet within a tubular casing whichgenerally communicates with a pipe like air supply conduit the wholeconstruction of which is sirable volume of sound. Also itis foundthatcertain boilers have different requirements as to the relative value ofsteamand air supply and generally the rate of supply of steam isadjusted to suit the requirements of the boiler as far as possible butthe regulation of the airsupply is not adjusted with respect to each jetso that the desired result is not always obtained. The object of myinvention is to provide a construction of blast apparatus for furnaceswhich will not have these disadvantages. p

In v order that this invention may be clearly understood and readilycarried into effect two sheets of drawings are appended heretoillustrating embodiments thereof and wherein,

Fig, 1 is a longitudinal sectional view of one of the jets. I

Fig. 2 is a side elevation the device shown in Fig. 1. V

Fig. 3 is a detail sectional view to a larger scale showing the devicefor regulating the quantity of steam flowing to the jet.

Fig. 4 is a partsectional coupled pair of injectors. H i

Fig. 5 is a part sectional front elevation view showing a modifiedarrangement of smoke eliminators which are particularly adaptabletoboilers fitted with mechanical stokers, and 7 Fig.6 is a verticalsectional View of acomplete assembly of one of the devices shown in Fig,5. j

Referring to the drawings, the blast apparatus comprises an air conduit1 open at one end 2 and closed by a plate 3 at the other and havingdirected laterally from it one or more chambers 4 each accommodating asteam jet 5 co-axially aligned with a Venturi tube 6 directed towardsthe furnace, the open end of the air supply conduit having disposedaround it a bell shaped cap 7 and having provided within it one ormorebafiles 8 for the purpose of producing a form of silencer, each'said jet.5having disposed about it a cone 9 provided with one or more air supplyapertures 10 each adjustable in effective area of opening.

In carrying the preferred embodiment of my view of the nozzle of planview showing a such as to producean unde-- .or directly aligned witheachother; .thesesaid plates canbe secured. in .one or more screws 12 passedthrough'the appropriate part of the air, conduit intothe within the boxand supported within a sleeve 14' fitted in a concentric tubular boss 15practice the air conduit can as shown in Fig. 4 be composed of anumberof flanged cast or drawn steel or iron tubeswith flanges ii attheir ends which are bolted together to providean air conduit of therequired axial dimension, each fiangedunitof this conduit having castintegral with it or welded to it a chamber invention into i in the formof a cylindrical box theaxis of which is at right angles relatively tothe axis of the air conduit 1. By constructing the. air conduit in thismanner a large amount of noise is eliminated as comparedwith existingapparatus in which the air conduit is made of sheet'metal. The plate 3is bolted against the outer flange at such end and the other ,end of theconduit iscomposed of a tube la from, which the box 4 and, the outerflange 11 are omitted. Fitted over itsouter end so to have an annularand an axial clearance therefrom is the bell shaped cast metal 'capFl sothat, the air entering saidcap has to reverse its direction, of travelto enter the. air conduit. Arranged diagonallyacross the interior of theairconduit at its inlet end is a bafiie 8 in the form of a plateprovided with a plurality of perforations as shown so that thecombination of this perforated plate and annular cap provides asilencer. If required more than oneof these diagonal plates can. beemployed, their faces being their apertures stepped relative to eachother Each of position by periphery ofeach plate. The bell shaped capcan be secured in position by one or more radial screws 13.

Each of the said. laterallydirected boxes 4 formed with the air conduit1 accommodates one of the steam jets 5preferably co-axially mountedconcentric formed integralwith the outer end ofv the box 4,

this concentric boss being normally closed by a movable cover cap, 16which can be hinged at one end on a screw threaded into .the outer endof the boxiand engaged at its other end by means of a hook shaped partover another like screw. The body of the steam. jet 5 is bored axiallyto receive an adjustable needle 17 in well known manner and the body 5is apertured between its periphery and its axis to provide asupplementary air passage 18. Air can pass through into an annular space19 surrounding the'support of the adjustable needle. and from thencethrough the passage 18 formed along the said body parallel with,itsaxis. This supplementary air can be admitted by opening the closureplate hinged at the outer end of the box. The inner end of the sleeve 14accommodating the jet is formed with a conical part 20 terminating in anozzle 21 parallel with and contiguous to each other and I fb'urning andby such an arrangement a cheap" the nozzle which drives the steam andair into r s to the jet body by a radial, pipe 25, threaded into thebody 5 andcarried through an. opening; pro-'- end to a conduit 23directed intothe required zone of the furnace. -.'I'his conduit mayhavea fiared downwardly inclined nozzle 24 detachably.

fitted onits free end as this part is subject to and easy replacement iseffected. Also the said flared nozzle can be composed of a metal oralloy of high heat resisting quality. Steam is admitted vided for suchpurpose in the side of the said box 4, and for the purpose ofregulating; the supply 1 of air the cone shaped front end 20 of the saidsleeveis' formed with a number of-longitudinal slots 26 and has-disposedabout it the Crim an throttle member i l-slotted: as at. 10toicorrespond with the slots.26;in-'theconical part of the sleeve.andform'ed with'a short cylindrical-portion 9'a at its inner end fittedover the correspondingly shaped part-of the said sleeve, a set screw 27being passed through afl'circumferential slot in said cylindricalportion into the said sleeve so that a fine adjustment can be effectedwith each I-jet.

.When, as wouldnormally be the practice a number of je'ts'and' theirassociated parts are provided a steam supply pipe 28 common to-.all ofthe jet pipes 25 is provided connected to the pipes 25 by suitable Tsand elbows in-well known Emannen. r, 1 1 When the invention-is appliedto .a'boiler fitted with mechanical s'tokers, the smoke eliminators canconsist of anumber of individual devices not .connectedto a common airconduit 1. Such'an arrangement. is shown in Figs. 5 and 6 in which.eachzbox 4 is formed with lugs4a by means of which it is. attached tothe boiler and plate. Steam'pipes 25' arecarriedto the jetsin'side' the.boxes 4 and each-box is formed an upstanding air conduit portionlbonwhich is bolted the tubular: member. 1a in the same manner. aspreviously described. In this arrangement; the bell members. 7 are''located above] the steam inljectors, the parts inthis embodimentcorrespond- -ing-to those in'the previously described embodiment bearingthesame referenc'e numerals The 'bell' shaped enclosing cap"necessitates ithe a'i'r entering the. inlet conduit following thesinuous course; and as the mouth of the bell shaped cap .isinjuxt'apositi'onto the said box the induced air :is ,toa certain extentpre-heated by-beingdrawn overthe said box before entering the air inletconduit, itbeing: understood that the said box iWill acquire aQCBItEJ-ILIdBEIQG-Of heat by reason ,ofthe location therein of thesteamjet. 1

The construction of; device shown in "Figs. -5 and 6 is intended :to.supply' steam and 1 air to a single nozzle and for -this ipurpose it ispreferred .to provide zwith-"theisteam supply pipe means [sagecan;.be.adjusted oneformed with a different ,the. furnace to be soconstructed that it sets up a turbulence action materially increasingthermal efficiency and the diminution of smoke, A suitable method ofobtaining this turbulence is to fit in the mouth. of the nozzle a numberof radial webs3l"which are inclined relatively to the axis of. thenozzleso as to impart a spin or whirling to the ejected steamand air. I g IThe shape and direction of the; nozzle 24- is preferably soarrangedthat-the delivery of the column of air crosses -over 'the'delivery of air from adjacentnozzles and sets up turbulence inthe-furnace, and the air is-pre-heated by-coming in contact withthenozales, allof whichincreases theefiiciency of combustion.

What-I claim is:

1 In a steam jet pump for deliveri and air into a furnace foreliminating smoke, a box an air inlet conduit extending laterally fromone side of said box, a steam jet accommodated in said'box, an outlet inone end' of i said box opposite which is located the emission end ofsaidjetya Ve nturi tube fitted in said outlet,'-a'n outer openinlet'endofsaid air conduit, anda substan- .-tial1y'-bellshaped capfitted overand'aboutthe said open inlet end of said conduit so" as to" be annularlyspaced-therefromso-as' to provide an annular air "passageabout the saidair conduit, k

a baflie in said air conduitj'said' bell [shaped cap having an openinlet located betweenthe'ends of the' air conduit; a steamand airemission "tube being fitted to theouter end ofsaidfVenturitube. I 2.In-a steamjet p'ump for delivering "steam and air into a furnace anairconduit open at one end and closed at the other, achamberintersecting said "conduit and projecting'laterally therefrombetween itsends,- a steam 'jet in said chamber; a- Venturi tube fitted'in one endof and directed from-said end of thejchamber towards the furnace,'saidjetbeing co-axial with said'venturi tube, a substantially bellshaped cap disposedabout and spaced from the open end of said air supplyconduit; and a baflle inside fs'aid I air supply conduit, the bellshaped cap surroundingathesaid airsu'pply'c'onduit' to provide anannular airspace, asteam andair' eniission tube beingfitted tothe'oute'r end of said Venr ei. 31 In a steam jet 'pump for delivering{steam and air into a furnace'an'air conduit o ener;

v steam oneen'd and closed at the otheri chambers inter secting saidconduit and [projecting laterally therjefrombetween its ends, steam jetsin said chambers-and'Venturi tubesin one of said-cha n'- bersfdirectedfromsaid chambers towards the furnace, said jets being coaxial with saidVeri- 'turi 'tube s, a 'substantiallybell shaped cap disposed about andspaced from the open end of a,

.said air supply t a baffle in Said airsmj;

ply conduit near its open end, the said bell shaped ca'p surrounding thesaid air supply conduitto fprovide a substantially annular airspace,;and i air and steam'emission tubes fitted to the outer 1 .ends ofsaid Venturi tubes. a I JAMES GARYIE.

